diff options
| -rw-r--r-- | arch/s390/kernel/nmi.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/arch/s390/kernel/nmi.c b/arch/s390/kernel/nmi.c index 3518ba638a85..b1579c85b869 100644 --- a/arch/s390/kernel/nmi.c +++ b/arch/s390/kernel/nmi.c @@ -114,9 +114,61 @@ void nmi_free_mcesa(u64 *mcesad) kmem_cache_free(mcesa_cache, __va(*mcesad & MCESA_ORIGIN_MASK)); } +static __always_inline char *nmi_puts(char *dest, const char *src) +{ + while (*src) + *dest++ = *src++; + *dest = 0; + return dest; +} + +static __always_inline char *u64_to_hex(char *dest, u64 val) +{ + int i, num; + + for (i = 1; i <= 16; i++) { + num = (val >> (64 - 4 * i)) & 0xf; + if (num >= 10) + *dest++ = 'A' + num - 10; + else + *dest++ = '0' + num; + } + *dest = 0; + return dest; +} + static notrace void s390_handle_damage(void) { + union ctlreg0 cr0, cr0_new; + char message[100]; + psw_t psw_save; + char *ptr; + smp_emergency_stop(); + diag_amode31_ops.diag308_reset(); + ptr = nmi_puts(message, "System stopped due to unrecoverable machine check, code: 0x"); + u64_to_hex(ptr, S390_lowcore.mcck_interruption_code); + + /* + * Disable low address protection and make machine check new PSW a + * disabled wait PSW. Any additional machine check cannot be handled. + */ + __ctl_store(cr0.val, 0, 0); + cr0_new = cr0; + cr0_new.lap = 0; + __ctl_load(cr0_new.val, 0, 0); + psw_save = S390_lowcore.mcck_new_psw; + psw_bits(S390_lowcore.mcck_new_psw).io = 0; + psw_bits(S390_lowcore.mcck_new_psw).ext = 0; + psw_bits(S390_lowcore.mcck_new_psw).wait = 1; + sclp_emergency_printk(message); + + /* + * Restore machine check new PSW and control register 0 to original + * values. This makes possible system dump analysis easier. + */ + S390_lowcore.mcck_new_psw = psw_save; + __ctl_load(cr0.val, 0, 0); disabled_wait(); while (1); } |